Re: [PATCH 0/4] perf tools: New comm infrastructure

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Wed, Sep 18, 2013 at 11:20:38AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Tue, Sep 17, 2013 at 02:54:22PM +0900, Namhyung Kim escreveu:
> > On Sat, 14 Sep 2013 08:11:49 +0200, Ingo Molnar wrote:
> > > * Frederic Weisbecker <fweisbec@gmail.com> wrote:
> > >> My patches and Namhyung's should improve the comm situation a lot but we 
> > >> can't do much miracle. The only way would be perhaps to be able to limit 
> > >
> > >> 
> > >> Now may be we can find other big contention point in perf. It's possible 
> > >> we also have some endless loop somewhere.
> > >
> > > Well, it was the 100,000+ step linear list walk that was causing 90% of 
> > > the slowness here. Namhyung's patch should dramatically improve that. I 
> > > guess time for someone to post a combined tree so that it can be tested 
> > > all together?

> > I pushed combined tree to 'perf/callchain-v2' branch in my tree

> >   git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git

> But you did it for some old tree, as I tried running it now and since my
> big perf.data file has PERF_RECORD_MMAP2 records, I can't try it with
> your branch, working on cherry picking those changesets, since a plain
> rebase didn't work.

Cherry picking just:

commit ad3c9edd70122c8776bc0735287daba3945e328a
Author: Namhyung Kim <namhyung.kim@lge.com>
Date:   Mon Sep 9 17:05:38 2013 +0900

    perf callchain: Convert children list to rbtree

I go from too-long-to-wait to:

[root@sandy ~]# echo performance > /sys/devices/system/cpu/cpu3/cpufreq/scaling_governor
[acme@sandy linux]$ taskset -c 3 perf stat --null --sync --repeat 3 perf report -i perf.data.make-j8-kernel > /dev/null

 Performance counter stats for 'perf report -i perf.data.make-j8-kernel' (3 runs):

      79.158464654 seconds time elapsed                                          ( +-  0.15% )

[acme@sandy linux]$
[acme@sandy linux]$ ls -lah perf.data.make-j8-kernel 
-rw-------. 1 acme acme 2.3G Sep 16 11:56 perf.data.make-j8-kernel

Looking at the other patches, modulo the ones that do the progress bar updating
while collapsing, as they clash with a patch from Jiri Olsa.

- Arnaldo